1. Field of the Invention
Aspects of the present invention relate to a β-sialon phosphor which can be used for a light-emitting device such as a white light-emitting LED (white LED) using a blue light-emitting LED (Light Emitting Diode) or an ultraviolet light-emitting LED (ultraviolet LED), the use thereof and the method for producing the same.
2. Description of the Related Art
Nowadays, along with the increase of the output of a white LED, the phosphor used for the white LED has been demanded to have a higher heat resistance and durability. A phosphor having, as a matrix, nitride or oxynitride which has a strong covalent character, has been receiving attention because such phosphor has small luminance change against temperature increase, and is excellent in durability.
Among nitride and oxynitride phosphors, Eu-ion activated β-sialon has been tried to be put to practical use, because it can be excited by light in a wide range of wavelength from ultraviolet light to visible light, and emits green light having a peak in a wavelength range of 520 to 545 nm, and thus is useful for a white LED (Patent Documents 1, 2). However, the luminance is not necessarily sufficient.